When inhaled, nanoparticles can elicit adverse cardiopulmonary health outcomes and their toxicity, particularly for metals and metal oxides, can be substantially greater than that of larger particles of the same composition. No standard measurement methods are available to quantitatively assess personal exposures to engineered nanoparticles, and without such methods, the extent to which workers are at risk from inhalation of nanoparticles is unknown. The laboratory work proposed in this research plan will standardize and validate measurement methods needed to quantify personal exposure to a range of metallic nanoparticles that are commonly incorporated into commercial products. We will develop an innovative nanoparticle deposition (NPD) sampler to collect nanoparticles specifically (separate from the larger particles in workplace air) and in a manner that reflects their deposition in the respiratory tract (Aim 1). We will also develop and validate a method to analyze the content of metal in the nanoparticles collected with the NPD sampler (Aim 2). These sampling and analysis methods will be easily adaptable by industrial hygiene practitioners to provide the system needed to assess worker exposure to metal nanoparticles. They will also represent enabling tools to study potential epidemiological relationships among metallic nanoparticle exposures and adverse acute health effects. PUBLIC HEALTH RELEVANCE: This work will result in methodologies to measure personal exposure to airborne metal and metal-oxide nanoparticles. As such it is applicable to assessing worker exposures to engineered nanomaterials in the burgeoning field of nanotechnology.